Mercury vacuum-pump.



H. A. PL'BUSS. MERCURY VACUUM PUMP. APPLIOATION FILED 11113.10, 1911.

991,493.l Patented my 9, 1911.

lin

5 the tube a but which is removed when lling i HENRY ALBERT FLEUSS, OF THATCI-IAM, ENGLAND. MERCURY VACUUM-PUMP.

991,493., Specification of Letters Patent.

Application filed February 10, 1911.

Patented May 9, 1911. Serial No. 607,742.

sage o with mercury. .a is a passage from the side of the tube b into the lower end of Vthe pipe Z which at its upper end is connected with the vessel to be exhausted. m a valve for preventing mercury from passing up- To all whom t may concern:

Be it known that I, HENRY ALBERT FLEUss, a subject of the King of Great Britain, re-

fu mprovements in Mercury Vacuumward into this pipe. n an inner tube closed Pumps, of which the following is a speciicaat top but with perforations in its sides to tion.

serve as a baffle by which should there be any sudden upward rush of mercury and should the mercury which so passes the valve is stopped. o is a valve pressed downward by a coiled spring p against a valve seat g at the upper part of the tube Z2. r is a chamber above this valve seat. s is a cap by which the top of the chamber is closed. The cap has a central passage formed through it closed at the top by a cap t. u is an overflow pipe passing from the upper end of the chamber r to the tube a: at a level above the mercury in this tube. In Fig. 2 this tube is shown in dotted lines as it would have been cut away in making the section. o is a pipe led downward from the upper part of the tube a to a mercury trap or catch pit w (see Fig. l and in dotted lines in Fig. 2) from which a pipe m extends to the suction inlet of a secondary air pump which may be of any ordinary construction.

When filling the lower part of the tubes a and Z) and the passage c with mercury the piston is brought to the top of its stroke, the cap t is taken olf and the rod y is taken out. The plug j which closes the overflow outlet from the tube a is also removed. Mercury is upper chamber and in which some mercury is at the end of the upward rise of the mercury also caused to pass the valve.

My improvements are hereinafter described with reference to the drawings annexed and are specifically claimed at the end of this specification.

Figure l is a horizontal section, Fig. 2 a vertical section through the line A-B Fig. l, and Fig. 3 a vertical section through the line C`D of parts oi a pump in which all my improvements are embodied.

a are two vertical tubes connect-ed one` with the other at the bottom by a curved passage c.

is a piston rod passing downward through a stuffing box e carried by a cap f which closes the upper end of the tube a.

g is a piston on the lower end of the piston ro L is an oscillating lever arm coupled at its p end by links z' to the upper end of the piston j maining closed by the pressure of the spring rod and by which this rod has an up and f upon it. The mercury lirst fills the chamber down movement given to it or other means might be adopted for giving an up and down movement to the piston.

In Fig. 2 the piston is shown at the top of its stroke. 7c is a iloating valve closing a passage formed through the piston and preventing mercury from passing upward through this passage but which if it drops from its seat allows mercury to pass downward to fill any space which may be left bepipe u to the interior of the tube a and passing downward through the piston lls the lower parts of the tubes a and until the mercury has risen in the tube a high enough to il tween the upper surface of the mercury in it reaches the overliow outlet from which the tube a and the underside ofthe piston the plug j has een removed. when the piston is at the top of its stroke. l When mercury liows out from the overj is a plug closing the overflow outlet from the lower parts of the tubes a and the pasr and then liows down through the overliow only is the valve'always kept covered with Y mercury and air excluded from passing back through it but in addition any dross floating on the surface of the mercury in the tube b will at the end of its upward rise in this tube be carried past the valve 0 and will then float on the surface of the mercury in the chamber 7' and as more mercury passes into the lower part of this chamber the dross together with mercury will pass down through the overflow pipe u into the tube a above the level of mercury therein and the drossthen floats on the surface of the body of mercury which always remains above the piston which works in this tube and is thereby kept from again becoming mixed with the main body of the mercury.

From time to time the dross may drawn either through from the tube a which normally is closed by the plug j or by opening some other outlet provided for the purpose at a somewhat lower level at a time when the piston is held be withthe overflow outlet at the upper end of its upstroke.

v upward into the air inlet pipe Z.

If the pump be made of sufficient height a seondary vacuum pump may be dispensed wit The action of the pump is as follows When the piston g is forced downward mercury is caused to rise in the tube b, when it rises in this tube to above the level of the air inlet .e it floats upward the valve m and mercury is thereby stopped from passing As the mercury continues to rise it sweeps upward all air that is above it and discharges it past thevalve o into the chamber r, some of the mercury being also caused to rise up into Vthis chamber. A quantity of mercury equal to that which has been so caused to rise up into the chamber r flows down from the chamber through the overliowV pipe u to the tube a above the level of the mercury therein. There is therefore always a column of mercury above the valve 0. There is also always more than sufficient mercury above the piston g ready to flow downward through the piston past the valve k when the piston comes to the end of its upward stroke and fill any space which there may then be between the bottom of the piston and the surface of the mercury which is below the piston. At the end of each up- Y ward stroke of the piston there will always be a space below the piston to be thus filled with mercury from above the piston byreason of some mercury on the previous down strokev of the piston having been driven past the `valve o and conducted back to above the piston by the overliow pipe u.

ln the above way I not only insure that a uniform quantity of mercury shall be forced past the valve 0 on each Adownward stroke of the piston but also insure that when the piston commences each downward stroke its under side shall be in close contact with the mercury below it so that when the down stroke commences the mercury below it will be started into motion without y any blow or shock.

That l claim is l. In a mercury vacuum pump the coinbination of a vertical tube or pump barrel, an air inlet pipe opening into the lower part of this tube or pump barrel, an outlet valve at the top of the pump barrel always pressed downward toward its seat, an upper chamber into which the valve opens, means for causing mercury to alternately flow downward from the tube or pump barrel to below the level of the air inlet and to rise up past this air inlet and to fill the tube or barrel and cause some mercury to pass the outlet valve into the upper chamber and an overflow passing from this chamber at a higher level than the valve.

2. In a mercury vacuum pump the combination of a vertical tube or pump barrel, a descending vertical air inlet pipe opening at its lower end into the lower part of this tube or pump barrel, a valve at the lower end of the vertical inlet pipe to prevent mercury from pressing up from the pump barrel into this pipe, an outlet valve at the top of the pump barrel always pressed downward toward its seat, an upper chamber into which the valve opens, means for .causing mercury to alternately how downward from the tube or pump barrel to below the level of the air inlet and to rise up past this air inlet and to fill the tube or barrel and cause some mercury to pass the outlet valve into the upper chamber and an overflow passing from this chamber at a higher level than the valve.

3. ln a mercury vacuum pump the combination of a vertical tube or pump barrel, an air inlet pipe opening into the lower part of this tube or pump barrel, an outlet valve at the top of the pump barrel always pressed downward toward its seat, an upper chamber into which the valve opens, a second tube connected with the lower end of the first, a body of mercury filling the lower part of both tubes and the connection between them, a piston immersed in the mercury in the second tube, means for giving a to and fro reciprocating movement to this piston and an overliow passing from the upper chamber at a higher level than the outlet valve to the upper part of the second tube.

4. In a mercury vacuum pump the combination of a vertical tube or pump barrel, an air inlet pipe opening into the lower part of this tube or pump barrel, an outlet valve at the top of the pump barrel always pressed downward toward its seat, an upper chamber into which the valve opens, a second l tube connected with the lower end of the first, a body of mercury filling the lower I end of the second tube, a catch pit or mercury-trap at the lower end of this pipe and the suction pipe of a secondary pump passing from the upper part ofthe catch pit or tra 61.3111 a mercury vacuum pump the combination of a vertical tube or pump barrel, an air inlet pipe opening into the lower part of this tube or pump barrel, an outlet valve at the top of the pump barrel always pressed downward toward its seat, an upper chamber into which the valve opens, a descending air inlet pipe opening at its lower end into the lower part of this tube or pump barrel, a valve at the lower end of the air inlet pipe, a second tube connected with the lower end of the first tube or pump barrel, a body of mercury filling the lower end of both tubes and the connection between them, a piston immersed in the mercury in the second tube, a stuling boX at the upper end of this second tube, a rod extending upward from the piston through this stuiiing boX, an overflow passing` from the chamber above the pump barrel to the second tube at a level above the level of the mercury therein, a passage through the piston and a valve closing upward iiow of mercury through this passage, a pipe carried downward from the upper part of the second tube, a catch pit or mercury trap at the lower end of this pipe and the suction pipe of a secondary pump passing from the upper part of the catch pit or trap.

HENRY ALBERT FLEUSS.

part of both tubes and the connection between them, a piston immersed in the mercury in the second tube, means for giving a to and fro reciprocating movement to this piston and an overflow passing from the upper chamber at a higher level than the to the upper part of the second tube, a passage through the piston and a valve closing upward flow of mercury through this passage.

5. ln a mercury vacuum pump the com` bination of a vertical tube or pump barrel, an air inlet pipe opening into the lower part of this tube or pump barrel, an outlet valve at the top of the pump barrel always pressed downward toward its seat, an upper chamber into which the valve opens, a second tube connected with the lower end of the iirst, a body of mercury filling the lower part of both tubes and the connection between them, a piston immersed in the mercury in the second tube, means for giving a to and fro reciprocating movement to this piston and an overflow passing from the upper chamber at a higher level than the outlet valve to the upper part of the second tube, a passage through the piston and a valve closing uplvitnesses:

ward flow of mercury through this passage, l RIPLEY WILSON,

a pipe carried downward from the upperl W. L. TAYLOR.

Copies of this patent may be obtained for ve cents each, by Washington, D. G.

addressing' the Commissioner of Patents, 

